White House officials plan to announce Sunday that improvements to HealthCare.gov were in place by Saturday’s deadline, the Washington Post reports.

The upgrade was completed about 4 a.m. Saturday, the Post says, quoting a government official familiar with the project, who spoke on the condition of anonymity to describe details that the administration was not publicly disclosing.

Improvements include expanding the site’s capability to handle up to 50,000 users at once, but officials are still scrambling to meet internal deadlines to repair the federal health care site. And officials will not know exactly how many consumers it can accommodate until more consumers begin to use it, the report shows.

On Friday, government and outside technical employees worked through the night on the latest upgrade to improve the site’s capabilities for consumers who want to register for an account and then log in.

The Obama administration, chiefly Health and Human Services Secretary Kathleen Sebelius, faced a chorus of criticism after the site’s Oct. 1 launch was dogged by glitches, including complaints from consumers about logging onto the site. The completion date was extended to Nov. 30 to give workers time to make repairs.